Does the seal of confession apply even when the sin is intended and there is no desire to repent? Forgive me if this is too basic, I am no theologian, and I was puzzled by a scene from a popular TV series about a crime-busting priest. In it, the villain goes into the confessional and informs the priest of a crime he is planning to commit in order to silence the priest. The priest asks if he intends/wants to repent, the other says absolutely not, but "you can't tell anyone!?"

From my long-forgotten religious education, I would suggest that simply telling a priest you intend to sin would not constitute confession, and therefore the "seal of the confessional" simply would not apply. Of course, for dramatic purposes, the priest kept silent, but I doubt if he was bound to do so.

Welcome any more informed opinions.

Edit I have expanded the question, as, pace @Geremia, my question is not whether absolution is granted, as I believe silence would still be enjoined on the priest, but whether simply informing a priest that, eg, you are firmly determined to murder your spouse and have no "firm purpose of amendment" - would, in fact, constitute confession.
I can't find an explicit statement that the seal of confession applies (or not) to the "confession" of a sin to be committed in the future, but all the evidence suggests that it does not.

Canon 983 and 984 are most relevant regarding the seal of confession:


  Can. 983 §1. The sacramental seal is inviolable; therefore it is
  absolutely forbidden for a confessor to betray in any way a penitent
  in words or in any manner and for any reason.
  
  §2. The interpreter, if there is one, and all others who in any way
  have knowledge of sins from confession are also obliged to observe
  secrecy.
  
  Can. 984 §1. A confessor is prohibited completely from using knowledge
  acquired from confession to the detriment of the penitent even when
  any danger of revelation is excluded.
  
  §2. A person who has been placed in authority cannot use in any manner
  for external governance the knowledge about sins which he has received
  in confession at any time.
  
  Code of Canon Law


However, this presupposes that the confessor acquired this knowledge during a valid confession.

Regarding the essential parts of a valid confession, the Council of Trent taught that


  the acts of the penitent himself, namely, contrition, confession and satisfaction, constitute the matter of this sacrament, which acts, inasmuch as they are by God's institution required in the penitent for the integrity of the sacrament and for the full and complete remission of sins, are for this reason called the parts of penance.
  
  ...
  
  Contrition, which holds the first place among the aforesaid acts of the penitent, is a sorrow of mind and a detestation for sin committed with the purpose of not sinning in the future. This feeling of contrition was at all times necessary for obtaining the forgiveness of sins and thus indeed it prepares one who has fallen after baptism for the remission of sins, if it is united with confidence in the divine mercy and with the desire to perform the other things that are required to receive this sacrament in the proper manner. The holy council declares therefore, that this contrition implies not only an abstention from sin and the resolution and beginning of a new life, but also a hatred of the old...
  
  Fourteenth Session of the Council of Trent


Contrition in the penitent is required for the integrity of the sacrament, and contrition is obviously lacking in the case at hand since the "penitent" is not actually sorrowful and intending to avoid the sin in the future. Since it is not a valid confession it follows that the seal of confession does not apply. After all, if a priest overhears the villain disclosing his criminal plans outside of the confessional (e.g. discussing plans with an accomplice) he is obviously not bound to secrecy just because he happens to be a priest.

Even if the seal of confession did apply the priest is able to take certain measures to prevent the crime without violating the seal. I found an interesting blog post about the seal of confession (supposedly written by a canon lawyer) which explores some hypothetical situations similar to the one posed, the most relevant of which is:


  If the penitent is not willing to cooperate, there are sometimes
  situations in which priests can find ways to help the authorities
  without revealing the content of a person’s confession. If a penitent
  has indicated, for example, that he fully intends to kill or harm
  Person X, a priest may be able to warn the police that Person X is in
  danger, but without fully explaining how he obtained this information.
  I personally know of a case in which police received a phone call from
  a priest, warning them that two teenaged sisters were in danger at
  that very moment. The police understood that the priest was not
  permitted to give them more specific information, and simply located
  the girls, notified their parents, and made sure they were protected.
  It is quite likely that some horrible crime was averted by this
  priest’s action, yet he did not violate the sacramental seal—in fact,
  nobody was really sure if he had learned the information in the
  confessional or in a confidential conversation outside of it. Once
  again, such collaboration between the authorities and the clergy
  happens more often than we may realize.


Although the seal of confession probably does not apply in this situation, the penalty for violating the seal of confession is so severe that the priest may nonetheless choose to remain silent in order to make sure he does not violate the seal of confession.