The original concept for Mission Impossible was an agency that could find exactly the right person for any mission, no matter how extraordinary the talents needed, drawing on the entire population of the USA. In the end they usually used a small pool of recurring characters, but the original idea had some interesting possibilities.
Your mission, should you choose to accept, is to write a mission which requires the talents of at least one of the L&C characters, but NOT for the usual reasons. The only exception is that they do NOT want Superman involved - maybe they suspect that the enemy has Kryptonite, or have some other reason (such as planetary security) to keep him out of it
For example, the IMF might need a singer with good unarmed combat and burglary skills - enter Lois. Or someone who can pose as an expert on geckos, such as Clark.
Try to avoid the really obvious ones - yes, Jimmy's a good hacker but the US government already has all the hackers it needs - and anything that draws on the character's usual areas of expertise.
It'll help if you think how Mission Impossible episodes usually worked - something nearly always went wrong, and the most exciting moments were dealing with the problem without blowing the mission. Often the apparent problem was the moment at which the mission came together - for example, in one episode a criminal was knocked out and told that he'd moved several years into the future via cryogenics, exposed that lie and "escaped", but didn't realise that the real deception was that calendars had been moved forward a couple of days, so that when he went to collect his loot he was followed and arrested before the Statute of Limitations ran out the following day.
This post won't self-destruct in ten seconds, but it'd be cool if it did...