With the seris finale of hit CBS comedy "How I Met Your Mother" looming on the horizon, many fans are eager to find out spoilers about how the series will end. For the air date and spoilers from show creator and executive producer Craig Thomas, read on.

Craig Thomas recently spoke to TV Guide about what occurs in the series finale.

"[It] picks up right after Barney and Robin's wedding and becomes this time machine that takes us into the future. It tells the story of the 17 years between May 2013 and 2030, complete with many ups and downs," Thomas said.

Leaking another detail, Thomas told TV Guide that viewers can expect to see a guest star on the final episode. While he remained tight lipped about who the guest star would be specifically, Thomas did offer some hints.

The guest star will be "A fun, random one from the past," Thomas said.

According to Thomas, the end of the series had been planned for years, and when shooting the finale, producers did not divert from the paln.

"The very end of the episode - the last two minutes of it - is exactly what we'd planned out years ago. We even shot a part of the last sequence back in 2006 with Ted's kids, before they became the adults they are now," he said.

The series finale of "How I Met Your Mother" airs on March 31on CBS